How the earliest McDonald's restaurants were recreated for Michael Keaton's new movie

In "The Founder," Michael Keaton plays Ray Kroc, a struggling traveling salesman who goes from selling milkshake machines to becoming the mastermind behind expanding the McDonald's fast-food chain in 1954 after coming across the innovative hamburger stand created by brothers Richard and Maurice McDonald.

Taking the fast-paced kitchen and golden-arches design the brothers created, Kroc came onto the company as the person in charge of making McDonald's a franchise, and by the early 1960s he was responsible for expanding the company across the US. He ended up buying the company in 1961 in a shrewd deal for $2.7 million.

To accurately portray the origins of the McDonald's empire, "The Founder" director John Lee Hancock called on the services of two-time Oscar-nominated production designer Michael Corenblith to create the first restaurants for the movie.

Corenblith explains to Business Insider how he pulled it off.

"The Founder" is out in limited release Friday and opens nationwide January 20. In the UK on February 17.

"McDonald's No. 2 was built 50 minutes from where I live."

The oldest McDonald's in the world. Located in Downey, California.YouTube/Maplou

Corenblith began his research a month before production started. While he got his hands on training films, manuals, and reproductions of blueprints of the original restaurant designs that he got off eBay for $25, the last original McDonald's happens to be close to his home.

"It's in Downey, California, and it opened in August 1953 and has remained virtually unchanged in its exterior," Corenblith said. "So I had a working scale template."

Corenblith points out that the movie didn't have the approval or disapproval of McDonald's, so he did all of this under the radar.

The filmmakers decided early on to create only one McDonald's set, which would stand in for all the locations.

Sketch of McDonald's restaurant set.Michael Corenblith

"We took full advantage of the fact that every golden-arches franchise looked like every other golden-arches franchise," Corenblith said. "So we created the illusion that these were all individual restaurants that were popping up coast to coast when in actuality these were all clever reworkings of the exteriors of one built set."

The movie was shot in Atlanta, and Corenblith was tasked with finding a location within a 30-mile radius of its production hub.

The location that was finally discovered.Michael McFadden

"It becomes a needle in a haystack," Corenblith said. He took a month to find the right area. "We needed a location that was two parking lots wide and away from the airport so we're not interrupted recording sound."

The set was built in seven days.

It's built like a giant Lego set.Michael McFadden

"We built all of the standing elements in controlled situations in a warehouse," he said. "So essentially we had all the puzzle parts, but we had never seen the puzzle go together until we were actually out there in the execution phase. It went from an empty parking lot to something that was ready to be prelit and shot in a period of about seven working days."

All the restaurant scenes were shot in four days.

The finished product.Michael McFadden

Corenblith would change the background of the restaurant set and the alignment of parking lot spaces to make the set look like the different chains Keaton's Kroc character was visiting.

All scenes in and around the restaurant were done in less than a week.

The set featured a working kitchen inside.

Michael McFadden

The restaurant set had dual use as exterior and interior. It also featured a working kitchen. This led to a lot more red tape to deal with.

"We had to get permits to bring us up to almost restaurant standards," Corenblith said. "Water, heating, air conditioning, plumbing, electrical all had to be up to code because we were preparing food on set."

The filmmakers used tricks to get the camera inside the set.

Michael McFadden

Because space was limited inside the set, Corenblith came up with ways to film inside. Custom windows could be taken out so the camera would not have anything obstructing its view. And the kitchen was mobile.

"We could pull out selected pieces, so what looked like stainless steel countertops could be moved so the camera could fit inside," he said.

"I'm doing it for the fan base."

The Weinstein Company

Having done numerous movies based on real events, such as "Apollo 13," "The Alamo," and "Saving Mr. Banks" (in which he recreated parts of Disneyland), Corenblith is aware of how devoted some fans are to seeing a topic portrayed authentically. He strives to satisfy them.

"Whatever archival subject matter one takes on, there's going to be a community of people out there who have devoted a lot of their time and energy to understanding and to archiving it," he said. "So whether it's the Alamo or Disneyland, there's going to be a community of very committed people that are going to be generous of their time and resources. I'm really doing it for that fan base. It's important to me that they feel there's a responsibility to that group to get it as right as I know how to get it."